Hopper



July 4, 1939. G. KOHLHARDT HOPPER Filed June 17, 1937 IN VENTOR.wfi/Jdrr/f AT RNEY.

Patented July 4, 1939 UNITED STATES i ATENT OFFICE 1 Claim.

My invention relates to hoppers, and more particularly to a type ofhopper that acts as a reservoir supply chamber for material to be fed bygravity to an outlet at the bottom.

The object of my invention is to provide a means of preventing materialssuch as coal from arching across the bottom outlet, when used in stokersor the like.

Another object of my invention is to provide a means of permitting airto circulate around the materials so as to provide an even temperatureto the material, thus preventing one side of the hopper to feed fasterthan the remaining portion.

It is manifest to anyone familiar with the feed hoppers, such as areused in fuel stokers for heating plants, or the like, that the unevenshape of the fuel often causes an arch to be developed in which thematerial, due to gravity, causes the center portion to create a pressureon the outer portion causing it to force against the sides of thehopper, and preventing a steady feed to the bottom opening, in whichcase there is a lack of fuel supply causing an inconvenience as well asa hazard.-

The construction of my device is such that owing to its invert conicaldesign, the weight of the fuel or the like presses the fuel down causinga release in the pressure against the sides of the hopper.

The device is constructed in the form of an inner shell spaced andsupported inwardly from the outer shell to provide an air space betweenthe inner and outer shell and permitting the circulation of air therebycausing an even temperature around the entire inner hopper shellsupporting the fuel.

The invention consists of the following features exemplified in theaccompanying drawing in which Fig. 1 is a fragmentary cross sectionalview of the device as applied to a conventional type of stoker,illustrating the manner in which the inner invert conical hopper issuspended within the enclosure formed by the outer hopper.

Fig. 2 is a top view of the inner and outer hopper arrangement, and

Fig. 3 is a perspective view of an inner hopper constructed for acylindrical shaped unit.

Similar characters of reference indicate corresponding parts throughoutthe several views, and referring now to the same, the character Inrepresents an outer shell of cylindrical design such as is used as aconventional type of stoker hopper arranged to feed fuel to a screw typeconveyor H or the like, that will transfer the fuel to the fire box. Theconveyor l l is shown driven by a motor l2 attached to the conveyorshaft by means of a coupling I3. The top of the hopper ID is providedwith an extension l4 having a cover l5 hinged at IE to its Wall. Insideof the hopper shell I!) is shown an inner shell I! suspended from theouter shell ID by means of spacers l8 and I8 permitting air circulationat 10 IS. The spacers 18 are longer than the spacers 48' due to the coneshaped construction of the inner shell H which is smaller at the upperedge 20 than the diameter of the lower edge 2!. Bolts 22 are shown assupporting the spacers i8 and I8.

In operation the inner shell I! supports the fuel acting as a hopper tosupply the conveyor I l. The air spacer I9 between the inner shell lland the outer shell I!) permits the fuel inside the inner shell I! tomaintain an even temperature thus causing an equal feed of the fuelwhich slides down toward the conveyor H by gravity and the walls of theshell l1, being tapered larger at the bottom, provide easier slid- 25ing action and relieve the frictional resistance between the fuel andthe hopper sides.

The device is shown as cylindrical in structure but any desired shapemay be employed, as the principle adapts itself equally as well to arectarrgular or any other shape or hopper.

In the chosen embodiments of my invention there are present several newand useful features not heretofore shown in the prior art, but the rightis herein reserved to make such changes as are found necessary withoutdeparting from the spirit of the invention as set forth in the appendedclaim.

Having thus described my invention, what I claim and desire to secure byLetters Patent in the United States, is:

The combination with an outer shell of an inner hopper shell, said innershell being of conical construction having its lower edge greater indiameter than its upper edge, spacers attached to said inner shell, saidspacers disposed for suspending said inner shell from said outer shellpermitting air circulation between said inner and outer hopper shell,said outer shell terminating into a hopper at its lower end to receivematerial dispensed by gravity from said inner hopper shell.

GEORGE KOHLHARDT.

